The human eye is susceptible to numerous conditions that can deleteriously affect the crystalline lens. Certain diseases and disorders may also directly or collaterally cause damage to the natural lens of the eye thereby resulting is impaired vision and even blindness. Cataracts, for example, are opaque growths in the cornea that can arise as complication of diseases such as diabetes. Cataracts can also arise simply due to the effects of aging. Fortunately, modern medical science is capable of assuaging the most severe consequences of lens damage and providing patients suffering from such with a renewed outlook on life. The procedure for accomplishing this is surgical removal of the damaged natural lens and its replacement with a polymeric artificial lens referred to as an intraocular lens or IOL.
An IOL can be implanted in the eye as a total replacement for a damaged natural lens, as would most often be the case with cataract surgery or it may be implanted to provide vision correction in an eye in which the natural lens is still functioning.
Generally, IOLs comprise a disk-like optic, which is the portion of the IOL that actually replaces or augments the function of the natural lens, and any number of flexible members or haptics that extend radially outward from the optic and affix themselves securely to portions of the eye to secure the position of the optic. Implantation of IOLs into the eye involves making a surgical incision in the eye which it preferably as small as possible to reduce trauma and speed healing.
Early generation IOLs were constructed of rigid biocompatible polymers such as poly(methyl methacrylate)s. These lenses required relatively large and therefore undesirable incisions in the eye to insert them through. To deal with this problem, IOLs were subsequently developed that were deformable, i.e., flexible. Exemplary deformable IOLs are those made of silicone polymers and hydrogels. The deformable IOLs can be rolled into tubes or folded into various configurations, all of which present a substantially reduced profile for insertion into an eye. Incisions as small as 1-3 mm are common when such deformable lenses are used.
Numerous devices have been created and many others are proposed to aid in the insertion of the rolled/folded IOL into an eye. In one current manifestation, the IOL is first folded into a shape resembling a taco and then is pushed through an insertion cartridge or “insertion tip” whereby it is progressively rolled into a tubular shape in which conformation it can be readily inserted into an eye through a miniscule incision such as that mentioned above. Due, however, to the nature of the polymers used for the deformable IOLs and those used for the insertion device, significant frictional forces often arose between the rolled IOL and the polymer of the insertion tip. This friction too often could result in damage to the IOL, even to the point of rendering it unusable, in which case the procedure had to be repeated.
What is needed is an insertion cartridge or tip that is more lubricious than those currently in use so as to facilitate the transfer of the IOL from the insertion device into the eye. The present invention provides such a lubricious device.